These channels are a part of GT12:
3+
3+ Movies (formerly 4+)
3+ Series (formerly 5+)
3+ Crime (formerly 6+)
3+ Family (formerly 7+)
3+ Adrenalin (formerly TV24)
3+ Emotion (formerly TV25)
3+ Focus (formerly S1)
kabel eins HD
Nickelodeon
NITRO HD
ProSieben HD
ProSieben MAXX HD
Puls 8 HD
RTL HD
RTLZWEI HD
SAT.1 GOLD HD
SAT.1 HD
SIXX HD
VOX HD
More channels will probably be included in March 2023.
For all the remaining TV-channels Replay-TV remains unchanged including the option to skip ads.
You need more informations about GT12? Here you go.