How to do Contains or Starts with in a GI Expression

Is there any way to do a contains or starts with in an expression?

Google gave me some suggestions like using ‘LIKE’ or StartsWith([Field], ‘value’) but acumatica says its not supported.

I am trying to do a parameter for IIF the location ID contains or starts with a Q, then Remove the Q, and if not, leave it as is. 

Like this:

=IIf( ([INLotSerialStatus.LocationID] LIKE 'Q'), ([INLotSerialStatus.LocationID] - 'Q'), [INLotSerialStatus.LocationID] )

Or this:

=IIf( (StartsWith([INLotSerialStatus.LocationID], 'Q')), ([INLotSerialStatus.LocationID] - 'Q'), [INLotSerialStatus.LocationID] )

However, I cannot seem to find a way to do a contains expression.

Is this possible?