using proxies and such with accounts

Can I change dedicated proxies with accounts that used a specific proxy later down the road without it being flagged? Let's say I use a new dedicated proxy 2-3 months down the road?

Also, is it safe to log into the multiple accounts I created (if I have more than 5 accounts lets say) on a mobile device on mobile data?

I'm running ads Facebook account now , but I see running Google also, so no one needs , please contact me .