iOS briefly loses connection to Core

Bert,
maybe you could also try that, occasionally?

  1. Reset your iPads network settings completely
    Resetting these flushes caches and clears DHCP settings and other networking related info. To reset them, open the Settings app and navigate to Settings > General > Reset and tap on Reset Network Settings.
    Reconnect to your wifi network.
    In case your iPad is connected to a mobile network, disable.

  2. Renew Lease
    Lease renewing updates the address information of your network.
    To do that, tap on the information mark (i) next to your WiFi network name.

Tap “Renew Lease”.

  1. Set DNS settings to Google DNS and enter 8.8.8.8 and 8.8.4.4
    Here’s a link how to do that:
    https://www.macinstruct.com/node/452
    (It would be REALLY useful to set them in your fritzbox router as well!)
    Restart your IPad.

Fingers crossed that it will work … have a nice weekend!