Do I need to wait the 1-3 hours every time I reconnect to the pool?
What happens to my accepted shares from the first hours of mining?
No, it should save and pickup where you left off on that round. If not, you will still be paid.
some pools seem constantly DDoS'ed sucks
Pool has been up - only one DDOS occured here been running fine for 10+ hours @ 115MH/s.