7:30am flight - no need for a hotel room

[Manyindigowings]

Would need to leave for the airport at 4:30 to check in 5:30 for a European flight.,

Flying from Gatwick. I could get a train that arrives at Gatwick at 3:30am.

AIBU thar arriving at this time is a false economy?

Not sure you can check bags the night before for an EU flight. You will need to check with your carrier

Yes you can do twilight bag drop (drop bags between, l think, 8pm and 10pm the night before) for any flight departing before 8am at Gatwick. Have done this several times this year on European flights.