I want to book a flight from ATH to CGK via ZRH and FRA and it is booked in Z (Business Class).

I would like to book the following :

Day 1 - Swiss 1839 A320 ATH/05:15p ZRH/07:05p
Day 1 - Lufthansa 3735 32S ZRH/08:15p FRA/09:20p
Day 2 - Lufthansa 778 747 FRA/10:00p CGK/05:35p (+1d)

Is this classed as a stopover as the arriving ZRH flight is at 9.20PM and the departing FRA flight is at 10.00 PM the next day meaning its over 24 hours ?

But i cannot catch the FRA to CGK flight on Day 1 as the minimum connection time in Frankfurt is 45 mins and the connection time between the flights is 40 mins.

Can someone shed some light on this please

Thanks in advance .