Inconsistent Message Group Ids

[jesseschutt]

Hello and thank you for your efforts on this package! It's much appreciated.

I'm working in Laravel 8 on Vapor and am having some trouble getting the queued notifications to use different message group ids. I'm queueing notifications using the following as an example:

(new ReadyNotification($assignment))
    ->onConnection('fifo')
    ->onMessageGroup($assignment->getUuid())

My queue configuration looks like this:

'fifo' => [
    'driver' => 'sqs-fifo',
    'key' => env('SQS_KEY'),
    'secret' => env('SQS_SECRET'),
    'prefix' => env('SQS_PREFIX'),
    'suffix' => env('SQS_SUFFIX', '-develop'),
    'queue' => 'fifo.fifo',
    'region' => env('AWS_DEFAULT_REGION', 'us-east-1'),
    'group' => 'fifo',
    'deduplicator' => 'sqs',
    'allow_delay' => env('SQS_ALLOW_DELAY'),
],

As I've inspected jobs on the queue occasionally one will be on the {assignmentUuid} group but they are typically falling onto the default group as specified by the config above.

I've attempted to set the message group in the constructor of the notification but it results in the same inconsistent behavior.

What advice might you have as I continue to debug this?

Again, thank you for your time!