Glad to see you're on the semi barbed as theyre a lot easier on the pike, there is a real chance you'll deep hook pike especially as a novice pike angler, its something thats more common than a lot of folk let on
With the semi barbed and a decent set of long forceps then you'll be able to handle any eventuality, get yourself a pair of side cutting snips just in case theyre needed and as a bit of a confidence boost, it is very easy once youve got experience to remove hooks from a pikes stomach if thats where they end up but usually thats as a result of previous anglers snap offs leaving trebles/traces in the fish or water which eventually get picked up not usually down an individual angler on the day leaving it to long
The best way of avoiding issues like described is by using strong enough mainline and decent traces
How long to leave it?, well I guess if you're a half decent float angler to start with then you'll have a pretty instinctive idea as to when to hit the fish, if the float is wobbling from side to side it generally but not always means a pike has settled on the bait and is mouthing it (blowing it in and out) getting a taste before it decides to engulf it and swim away, if you see your float doing that then as soon as it dips and/or sails away then wind down to take up the slack line and hit the fish
I dont like the term "strike" because what happens is most folk give it big licks on the "strike" almost strong enough to damage the very thing youre trying to catch, dont use too big a hook and make sure theyre sharp
Some anglers I know use braid at 60 odd lb and meathooks for trebles and they'll hit the fish three or four times whilst the lines under pressure to ensure a good hook hold, big heavy guage hooks take some driving home whereas smaller size 8's and 6's if they're sharp take no more than firm pressure when you pick up the rod to set the hooks
Float movement is just another indicator in your armoury, your eyes are another, keep watching and if you see any unusual movement or if it lifts (lift bite generally means the fish has taken the bait and moved the weight) so be prepared to move fast and grab the rod
Its generally better to pick up your rod and hit the fish early and miss it than it is to let it develop and have to deal with a deep hooked fish, exactly how long and when you wait to hit it will only be gained by experience, forget all the old ******** about waiting for the second run or giving the pike minutes to turn the bait in its mouth, in my opinion advice like that which is still given is tosh, be prepared to lose or miss a few fish by hitting them early rather than waiting, a pike going belly up isnt what you want to be seeing
Good luck