30 GB in a backup takes a while, but it is also generally not a good idea. The bigger a file is the more likely that sometime during writing the file something goes wrong. I would recommend moving as many files as possible outside the backup ( enable sync instead for iCloud Drive, Photos, WhatsApp backup etc. that still requires the same iCloud space, but instead one big long process you have many tiny ones. That’s much safer and much less complicated.
Add the new card. Then remove the old one. If needed pay the outstanding amount using a gift card first.
I guess your iCloud space is not sufficient to make a backup and it hasn’t been for a year.
This is a normal expected battery health preservation feature. We had it constantly in my husband’s phone when we traveled to a warmer place and it is much more common if he uses his MacBook charger that is at the top range for wattage. It is not overheating just pausing the charging to allow for a longer time until you need to replace the battery. Nonetheless it can be quite annoying.
No one of he recent software versions fixed that.
Move to a colder country, charge with less wattage, place iPhone on heat conducting surface, don’t charge phone in bed, switch the stove off. At least 3 of the previous 5 may apply. 🥸
I forgot… if this is a 15 model: update to latest software.
Now we all want to know, if there is an actual thing in the code that suppresses that. I suggest a series of world wide tests because I fear for the sanity of tech support which would be the alternative.