Hi Aaron,
Of course I forgot to add what version we're running. It's BIG-IP 10.1.0 Build 3341.43 Engineering Hotfix.
Since it's above 9.4.4 I removed $:: but now I get a TCL error in ltm log.
local/tmm err tmm[4730]: 01220001:3: TCL error: new_maintenance - Invalid matchclass operands - no class or list type found, lhs: string, rhs: acl_maintenance (line 1) invoked from within "matchclass [URI::decode [string tolower [HTTP::uri]]] contains acl_maintenance"
And you're right in that our internal users should gain access during the maintenance for testing.
Confusing that I get the TCL error since I checked it several times now. The data list is there and it's named correct.
Thanks a lot for your help. Very much appreciated.