I believe the difference between the "2026 ALL SEASON DINING GOLD - ALL PARK* ADD-ON" and the "2026 ALL SEASON DINING GOLD - ALL PARK* UPGRADE" is that you can purchase the Add-on on its own while the Upgrade is for if you have already purchased a Home Park Dining Plan and wish to then dine at all of the parks.
For those who've been speculating: 2026 admission to Soak City is indeed included with a Gold or Prestige Pass. It says it directly in the pass comparison table on the purchasing page. That being said, it does not say "Unlimited Access to Soak City Water Park in 2026", which I'm sure us worriers will have a field day with. Similarly, Haunt and Winterfest are listed on the individual pass pages and the non-purchasing comparison page, but not on the pass comparison table on the purchasing page. Tricks and Treats is only listed on the non-purchasing comparison page. Nobody should have to go dig just to see all of their pass benefits — even if the pass is severely underpriced. Hooray for more discrepancies and unclear products, I guess
The omission of the Silver Pass from a lot of the parks pass lineups tells me that it may not have sold terribly well at parks that have Fall/Winter events. Gold and Prestige seem to have won out instead of Silver and Gold. Then there is also a discrepancy in which parks offer a Pre-K pass and which do not. Parks like Carowinds, Cedar Point, Kings Dominion, and Valleyfair all offer them while Kings Island is left without one (probably to keep pass sales up for that age demographic). Oddly enough, parks like Michigan's Adventure and Frontier City don't even offer 2026 passes at time of posting. Most of the Legacy Six Flags parks also still offer Park Membership programs with no sign as to if those will be going away anytime soon.
Even though I can understand why a chain would like to continually sell passes 24/7/365, I've now changed my mind and do not like that 2025 passes were still for sale within 1 week of 2026 passes going on sale. No disclaimers and no forewarnings of a future sale were put out on each website. Anyone who theoretically bought a 2025 Kings Island Gold Pass for $155 before today is now out of luck and paid $40+ for a product that is now irrelevant.
Speaking of websites, weren't we supposed to see new versions of the Six Flags websites and apps by some time in July? Here we are quickly approaching August with no sign of brand cohesion at all. Colin, from Coliwood Studios on YouTube, recently stated in a livestream that he's seen an early version of the new websites and that they look similar to the current Six Flags app; although he doesn't know what is taking so long to publish these new websites. I have a feeling that they may look similar to the current website for Six Flags Qiddiya City based on that comment, but nothing has been shown yet. Don't even get me started on the lack of the new-for-July Squishmallow that Kings Island has been teasing and advertising about.
The thing that frustrates me about this answer is that it is literally the same copy-paste answer that has been posted under every add-on question. Rather than allow someone to take a moment to actually sit and answer each question and tack this on the end with it, Six Flags seems to be forcing their social media people to paste this non-answer with no variation.
This is one of the only things I feel works better with the Park Membership model over the Season Pass model. With a membership you can (presumably) begin/end the membership at any time you please, and any add-ons could be set to expire rather than needing to void one pass to begin another. This pass sale roll out is losing its sense of desperation while beginning to reek from the stench of incompetent and/or inexperienced management. Why is a company whose passes have worked well enough for years now struggling to accomplish some of the most basic things? They can't even say this is an issue of combining benefits between the former chains because all of the 2026 passes use the Cedar Fair structure and benefits!
To add on top of all of this, we're also seeing the Legacy Six Flags logo on most 2026 pass marketing. Unless this is a tactic to allow for brand rehabilitation in the coming years, I don't know why they wouldn't choose to utilize the new logo that is supposed to show off the fact that this is a new, merged company.
Thank you @brenthodge for once again asking the good questions — even when they shouldn't need to be asked at all!