Hi Guys,
This is an interesting question that has several answers! Overall, the engine limits for the F, G and K versions of the Bf 109 were in a constant state of change. For example, the engines had many major changes, with 5 complete different types in more than 10 different versions of the engines!
So, Yes, there are differences in the printed documents and, I have not seen all the updated documents in 1943/44/45, I do not think they are all available. However, I will give a short bit of my info. The actual power settings names changed over time as well. Start. und Notleistung was Take-off and Emergency power setting. For the DB 605 A this was initially shown in the Flying Manual as a 1 Minute limit. However, in Summer 1942 shortly after operational introduction of the Bf 109 G, the S.u Not. rating was withdrawn on both the DB 605 and the DB 601 E because of problems with metal quality in the engine and some difficulties with sparkplugs etc. You can see this where the notes on the tables say "ist blockiert", (is blocked). So, not to be used.
This was not sorted until Autumn 1943 when the engine was released with modifications. This Autumn '43 release seems to have included the S. u Not. rating again, but now with a 3 minute time limit, as seen on some instrument panel markings. Later, in early Summer '44, the MW50 modifications were introduced with a full-power rating that allowed 10 minutes at max power with MW50 operation, with 5 min between the next use of MW50.
So, there are the basics, for the DB 605 A, 1 min on very early aircraft until no use above 2600/1.3 for over a year, then on modified engines, 3 min, then with MW50 upto 10 min.
Eng