There is quite a lot of swimming late in the day as pointed out by previous posters. However, given that she’s only at pre-school for 2 days, I’d say that doesn’t seem too much otherwise. It depends on how serious each of the classes is, I guess.
Before my daughter went to school, she was at nursery from 8-6 for 4 days of the week. She had ballet in the morning and gymnastics in the afternoon on my day off, then on Saturdays, she had football in the mornings and swimming in the afternoon. But none were very serious and all definitely just for fun.
Be aware that they can find the first term at school very tiring. Even with my daughter used to 9 hr days at nursery since she was a baby, she took herself off for an afternoon nap for nearly the whole first half term of Foundation Year. She was a very late summer born and just turned 4, so maybe that played a part emotionally, but I understand that isn’t that unusual. Apart from one activity after school, her other activities were all at the weekend during that period. I’m not sure how intensive the two evening swimming training sessions are, but I’m not sure how that would fit in with starting school.
Your daughter sounds a bit like mine - really keen to take things up, but less eager to give things up. She’s now doing 3 dance disciplines, 2 sports, swimming (just weekly lesson) and piano. She is desperate to continue them all, and is better disposed when she has many opportunities to burn energy off. This has exhausted parental ability to ferry her around, and she knows that to take anything new up, she needs to drop something else. I get the feeling that she would just happily collect activities endlessly if she were allowed to do so!
I can see a crunch point coming soon where each thing starts getting more serious/time-consuming. Also, I expect homework to be more significant from KS2 onwards. At that point, she will have to make a choice. It’s difficult as she really seems to love them all equally, doesn’t seem hugely talented at any one of them, but neither is she rubbish at any of them.
One top tip for the future if she wants to continue doing lots of stuff - try not to organise anything for a Sunday morning that could be done at a different time. It is prime territory for scheduling clashes between sports matches and show rehearsals, and you can do without having anything else to juggle then.