I don't believe anything was changed between those builds as far as the task scheduling goes. I only just recently started fixing/improving a few things in the task scheduler.
The default task setting is to run the scheduled task only when the user is logged in.
If you previously unchecked this setting and entered a password perhaps it has reverted to being checked again, or if the user account password has changed you need to update it.
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We've made some changes to the task scheduler in our latest beta releases, FlashFXP can now run scheduled tasks (with limited permissions) under the Service4User method and not require the user account password.