Hello Jason,
I believe that because your subscription was started after we'd already generated all of the orders containing Adventure Path 135 into active orders, your subscription order containing Adventure Path 135 never checked the sidecart for items which ship with it. This process only happens on the day the sub orders are authorized and generated.
In addition, the items currently in your sidecart were added there after this generation date as well, therefore they will not generate into an order to ship out on their own until the next subscription auth is run. This will happen on October 25th next, at which point it would join your November Adventure Path subscription order.
Generally the rule for sidecarts is that anything added to them will generate with the next newest subscription item. It will only join any currently pending orders or recently started subscription orders if CS moves them manually.
I can the sidecarted items out of the sidecart and get them to ship to you soon in their own order. Otherwise they will ship with the November volume in the next few weeks.
Please let me know which option you prefer. Thank you!