You must be lucky, but most people I know and from my own experience end up replying to email, slack or phone calls while on vacation and work piles up for them relative to how long they have been away.
Like I said, I hope you're compensated accordingly. Off time is off time, and being on call has a price attached to it. If you're being treated like you're on call but without the corresponding pay rise, that's called wage theft.
