In the past week or so my 4G has started taking between 7 and 15 seconds to connect and reconnect. It has always connected instantly before (this is while I'm at home, so surely the signal should be the same as it has been for the past 2+ years..?). It doesn't sound like long but it's getting quite frustrating having to wait for the delay with no connection sometimes. The VoLTE icon has also appeared for the first time on my phone in the last week or so, is this anything to do with it?
My phone is an S7 Edge, I've tried a cache wipe from the recovery screen, and switching network settings to only use 3G has the same delay. There was a software update recently but I can't remember if this issue began before or after that.