I read on the BBB that during character creation to begin play with a bounded spirit the max. services owed must be no more than the summoning skill.

Is this applicable to the bounded spirits during gameplay?, Max. services Owed=summoning Skill rating ?

What about unbound spirits?

No such 'in-game' limit that I am aware of.

Nor am I aware of a limit.

I did a cautious search before posting, nothing on the errata either.

I find some sort of "loophole" in this, however Im not sure about one thing:

Situation: a Magician summon a spirit and dont bind it, therefore the spirit is unbound
Question: Can u make the test again like if u were "re binding" it and get more task? Assuming summon a spirit only cost one complex, u might do this with a low lvl Force spirit and get lots of task; then u can easily sustain a spell for minutes even hours

No - you only get additional services from binding.

There is no 'resummoning' without dismissing the spirit entirely, and summoning a new one from scratch.

this make sense

The real reason you shouldn't be able to "re-summon" is that it blows past a very important limiter on mages. By RAW how many services you can get on a spirit of a given force is on one roll is how much you can get done for free. If you did it that way you would summon a spirit have it and get 4 services. You use that to possess yourself, and conceal, guard, and movement the whole team. pretty scary right there. But if you could re-summon you could get the spirit to influence every guard you come across, by getting one net hit on a re-summoning test. Also you could get the spirit to attack every encounter without dropping the buffs. Image that rather than ever cast stun-ball you just resummon and have your spirit of man use it's actions to stun ball every round until a group of hostiles are down. To do that under RAW you would have to get 5 net hits to use all the buffs and have a task left over to order the attack. Also you would have to waist several rounds re-casting them.

You can only rebind spirits, not resummon. That said, how much money you got? Binding materials cost! Sprites on the other hand...