I have had 2 mugs of Coffee, before I post this:
Last week, I redeemed my JP Miles on a domestic S2 flight ex-BOM. Now, everyone knows, that the S2 flights are a royal pain if one needs to check-in online or assign seats.
The S2 bookings on 9W stock have always had an alternate PNR. You can see the difference on the eTicket & BP. The alternate PNR was no good for OLCI / seat selection. But that seems to have changed now.
With less that 48-hours to STD, I called up Jet to tele-check-in. I was transferred twice to the 'Domestic' desk and then finally the agent asked me to attempt OLCI with an alternate PNR.
I stayed on call, while I selected seats and checked-in online and got a copy of BP swiftly.
Yes, Jet has just shown an IMPROVEMENT..! 
Or is it just a myth..?