Trying to book a redemption booking as follows:

MNL-SIN (J class) - 2 class flight
Transit
SIN-SFO (F class) - J class not available on saver

SFO-SIN (J class)
Stopover
SIN-MNL (J class)

Any idea if I am able to call in and get the above issued on 1 ticket (to avoid YQ even on the return trip since the ticket is ex-MNL) but get SQ to charge one way F class rate (91,375 miles) and one way J class rate (68,000 miles)? I am wondering if the agent will insist on charging as a round trip F class redemption.

If yes, I believe the system prices it as two 1 way tickets, so I am not entitled to any complimentary stopover and have to top up 100USD to stop in Singapore on the return?

On a side note, with the latest update to the website, it seems that the multi-city button for redemption bookings (which also used to allow selecting a stopover) is now gone? I still see it for commercial bookings.

Thanks!