The Pennyroyal Tea single was recalled shortly after Kurt Cobain's suicide [1,2]. At that time the German CD single was the only retail version which had been distributed, or perhaps even manufactured. Recalled singles were destroyed [1,2,3], but several escaped destruction.
The title track was remixed by Scott Litt. The bass guitar and backing vocals are more audible, and the cough at the start was removed. The remix was also available on the edited American versions of In Utero on CD (DGCD-24705) and cassette (DGCC-24705), which was sold at Wal-Mart and K-Mart. A remastered version was later released on the 2002 Nirvana compilation. I Hate Myself And Want To Die originally appeared on the Geffen/DGC compilation The Beavis And Butt-Head Experience, while Where Did You Sleep Last Night was later released on Unplugged In New York, and also on the Nirvana compilation.
The track times listed on the disc are incorrect. The actual track times according to my stereo are 3:36, 2:43, and 4:53, respectively.
Rob Fellows, an MCA UK sales representative, stated that the release date in the UK, where they would manufacture their own domestic singles, would be either Monday, March 28th, or Monday, April 4th, for all formats, to coincide with the British tour.  This is also supported by a newsletter sent to those who returned the form included with the British All Apologies CD single (GFSTD 66), shown in image 9 (left), although the A-side was not yet decided at the time the newsletter was sent.
In the UK they would usually present the single for presale to retailers two weeks ahead of the intended release date, but Fellows did not recall that the sales team ever did that. This was most likely because of Cobain's overdose in Rome on March 3rd. As a result of the overdose, the rest of the European tour was rescheduled. The single was still supposed to be manufactured, only slightly delayed to coincide with the new British tour dates, as can also be seen in the second newsletter in image 9 (right).  The single was ultimately cancelled as soon as Cobain was found dead [1,2].
The single was cancelled because the record label did not want to be seen as cashing in on Cobain's death [1,2], and the title of the B-side,
I Hate Myself And Want To Die, did not help matters . Fellows recalls that retailers requested Nirvana releases following the suicide, but they were declined out of respect for Cobain. 
Retail singles were most likely not manufactured in the UK [2,3], but the German CD singles were manufactured and distributed, or at least sent to the distributor, by the time the release was cancelled . The original release date was probably approximately the same as in the UK. Whether they were sold by retailers is uncertain, but it is possible that some were. The singles in distribution were recalled, destroyed, and disposed of by the record label or distributor [1,2,3], or destroyed on site by the retail outlets. A record store owner in Stockholm reported that singles were destroyed in Kista outside Stockholm . A person working in a distribution center in Holland reported that singles were destroyed in presence of people from the record label . In both cases store and distribution employees managed to put some copies aside. This seems to be the main reason that some singles survived; not that they were sold in stores.
The German CD singles were manufactured by Sonopress in Gütersloh, Germany, as identified by the matrix and IFPI codes. There are three major variants; one without IFPI code, one with IFPI 0793, and one with IFPI 0738. Of the discs without IFPI code, there are discs with a ring in the plastic close to the spindle hole (image 4), and discs without this ring (image 5). IFPI 0793 discs also have this ring (image 7), while IFPI 0738 discs do not (image 6). Discs without IFPI code have a melted effect in the plastic around the rim (image 8), while at least IFPI 0793 discs do not. This is common for many Sonopress pressings. The metallic reflective layer varies a little in size between the discs without IFPI and IFPI 0738 variations, by extending closer towards the rim on one of them.
The first two digits in the IFPI code identify Sonopress, while the two last identify the specific mould which pressed the discs . This means that the singles were pressed in at least four different moulds, considering that there are two variants without IFPI code; they must have been pressed in at least two moulds without IFPI codes fitted. IFPI codes were first introduced in late 1993 , and this is one of the first Nirvana releases to have an IFPI code. The reason that singles without IFPI codes exist is probably that Sonopress had not yet had time to fit the codes on all of their moulds. IFPI 0738 is the rarest variant. Only three have appeared, all found in Holland.
Most of the German singles were distributed by BMG in Holland and Germany, at least this seems to be were the most singles were found. However, in 1999, a large amount of singles started to appear on eBay, all sold by South Korean sellers . They were all of the IFPI 0793 variation, put in resealable plastic bags. One of the sellers stated that a South Korean import company imported 200 copies, but it is hard to imagine how he got that information. The real number is likely higher, 200 is a very small number to import. From price tags on the discs (image 9), it seems the discs were distributed through regular channels by BMG. While it is uncertain exactly what happened, it seems the discs were not recalled in South Korea, or the recall was less effective, and the singles were sold by retailers in 1994. This makes sense, as the discs would have to have been shipped a certain time in advance. At some point some people must have realised that the singles were collectors' items in Europe and North America, stocked up on singles, and started selling them on eBay. This theory is supported by the seller which sold the most copies on eBay. He said he found the singles in various shops for very different prices .
Further, before these surfaced on eBay in 1999, no discs with an IFPI code were known of. It is possible that it had just gotten unnoticed, but it is possible that the IFPI 0793 batch was manufactured entirely for South Korea
Other countries would also have imported the singles. The German CD singles would have been sold in most of Western Europe, except in the UK and France where Geffen would have manufactured domestic releases, going by previous singles from In Utero. The last few Nirvana singles had not been manufactured and officially released in the USA, but the European CD singles were imported by stores. In the USA, only promotional CDs would have been made, and maybe also promotional 12" vinyl records, again going by previous singles. In Australia, domestic CD and MC singles (GEFDM-21907 and GEFCS-19220) would have been made judging by previous releases, but Australian stores often imported European or American releases to sell while waiting for the domestic pressings to be ready . Official Australian release dates were often later than the rest of the world. Importing was in fact often cheaper for the Australian stores (which would charge extra for imports nonetheless), but strict import laws designed to protect the domestic manufacturing industry prevented full scale importing. 
There is one counterfeit, known as the plus-version from the matrix code. It has been around at least since 1995 . Information about this is supplied in the list of unofficial releases.
Because of the unknown circumstances around the IFPI 0793 singles which appeared in South Korea, some people believe the IFPI 0793 pressing to be counterfeit. While the story around it may be uncertain, the manufacturing details are not. The discs are indisputably legit. The matrix code is identical to other Sonopress matrix codes from the same time, the ring in the plastic around the spindle hole has been observed on discs pressed by different Sonopress moulds, and the standard Sonopress feature where the metallic reflective layer is not perfectly centered around the spindle hole is in place. The disc label print quality is the same on all variations.
The inserts have also been inspected to be identical. For example, the transparent coating applied to give a slight glossy appearance at the top 5 mm appears defective. The same defect is on inserts from discs with and without IFPI codes. This would be impossible to reproduce. The slimline cases are also identical, down to the small E.2.8/ E.2.7 codes on the back. 
1. Front of insert
2. Back of insert
4. Matrix without IFPI code, with ring
5. Matrix without IFPI code, without ring
6. Matrix with IFPI 0738
7. Matrix with IFPI 0793
8. Melted edge (no IFPI), and clean edge (IFPI 0793)
9. Single with South Korean price tag
10. Tour info, original and updated newsletters