Originally Posted by
Jeedos
Correct, this is my strategy too. Booking the highest category of single room has always guaranteed a suite upgrade.
However, some ICs do not automatically grant Club Access to suites - so double check with the individual hotel

Individual hotels can of course go beyond but per T&C, lounge access is only granted if you pay for it, you can be upgraded to a club room without club access...
16. The InterContinental Ambassador guaranteed one room category upgrade excludes Club InterContinental or Regent Club experience/lounge access. Should a member’s original room purchase be one category lower than an advertised Club room/suite category, the member will be assigned the one category upgrade without the Club InterContinental or Regent Club experience/ lounge access.