We're just two weeks from the final 'How I Met Your Mother' premiere of "The Locket / Coming Back," and we're still not entirely sure how the long-running CBS comedy's final year will divide story between multiple timeframes over Barney and Robin's wedding weekend. Now, executive producer Carter Bays has come out to defend the decision to try "Something New," while a new promo for the season reveals even more of the long-awaited mother!

Speaking to Zap2It, Bays clarified that he and co-creator Craig Thomas had originally intended to end the series with season 8, but Thomas' idea to shake things up by exploring the story ideas to come out of introducing the mother at Barney and Robin's wedding, both during and into the future, ultimately started a creative snowball that led both creators to fight for a ninth season. That said, Bays admits that the prospect could be hard to swallow for longtime fans, at least until they see what writers have come up with.

We wouldn't have devised this season if we weren't planning on seeing [Ted and the mother together] in some way. I wouldn't want to give it away, because it's a fun device, the way that we explore her life.

But yeah -- the whole "it's going to be the weekend before the wedding" thing, I get the reaction. If you haven't been in the writers' room with us cooking it up and you just hear that, you'd think "They're just pushing back the end-zone line." [Like] we're just waiting and it's going to be 23 episodes of spinning our wheels.

I think it will be clear in the first two episodes -- we're getting to write stuff that we haven't been able to write and have been wanting to write for many years now.

Meanwhile, the final season of ‘How I Met Your Mother’ has recruited such guest stars as ‘True Blood‘ star Anna Camp (replacing ‘The Office”s Ellie Kemper), ‘Revenge‘ star Roger BartSherri Shepherd, and has Wayne Brady and John Lithgow reprising their roles as Barney’s half-brother James and biological father Jerry. Bays even jokingly compared the final season to 'LOST''s time-travelingly trippy fifth season, in that multiple facets of the show's timeline would be revisited. In addition to the latest promos, clips and photos, CBS previously revealed that all four regulars would meet the mother prior to Ted, something we saw Lily do in the latest.

While we count down to next-next Monday's premiere, check out an all-new promo with more of Lily's interaction with the still-unnamed mother (Cristin Milioti), and tell us what you want to see from the final season of 'How I Met Your Mother' in the comments!