Yet again, I've had a transaction disappear after I linked it to a recurrence.
A charge that still appears on my Bank of America account was visible in my Simplifi transactions and had cleared. I never mess with transactions until they have moved from Pending to Cleared on Simplifi's end.
The expense was 1¢ off my monthly recurrence, so I manually linked it by going to the appropriate Upcoming transaction in my Spending Plan / Bills. I remember linking it to the correct transaction and seeing it was linked correctly just yesterday.
Today the transaction is completely gone and the expense is again listed in my Spending Plan as Upcoming. I am not able to find the transaction at all on Simplifi through the transactions ledger. It is still cleared on my account.
Last time I was in touch with Support on this issue, I went through a rigamarole of screenshots, logs, making my account manual and then re-linking it. I've also deleted recurrences and re-started them.
As has been reported by other users with Closed discussions, this seems to be an issue with Simplifi. I should be able to trust Simplifi rather than needing to audit it for missing transactions.