On first time connection to R500 took very long time for iANYTHING to get dhcp address from AP. This problem do not exist for Android and Windows.
Previously reconnecting was impossible for iphone/ipad. Today I turned off most of nice AP features, keep channel thin, use only one channel, and only one SSID, and looks like maybe it will work - still testing it. Interesteing that when I had 2 SSIDs problem occured again.
Still when device goes out of sleep mode takes them a lot of time to reconnect.
When I reconnect to old net, all devices are connect within seconds