....although I'm not on bail for charges.
Perhaps you were on unconditional bail.
In which case, it is more likely that the warrant was issued for "Fail To Appear",
rather than for "breach bail conditions".
It won't take much for you to be arrested next time you come under notice.
All it will take is for a constable to "run the usuals" on you at RBT,
or at a vehicle stop for speeding, and you'll be looking at immediate arrest,
and quite possibly highly conditional, or even refusal of, further bail.