Your software
My Mautic version is: 3.2
My PHP version is: 7.3
My Database type and version is: Mysql
Your problem
My problem is:
More SMS painful fun / learning
Question 1
Is there a way to speed up SMS sending? multi threading?
Question 2 - Any experience such as below with SMS? First large SMS run through Twilio
Some how my server ran out of pip threads and the campaign froze, restarting php and litespeed then retriggered the campaign to resend a couple 1000s SMS 
Doesnt appear to have the same protection systems for SMS as it does for Email in campaigns (Not fun discovering)
Confused as hell as the SMS was scheduled, the campaign timeframe timed out as we had it live for 3hrs (didnt want to double send to new enquiries for which we had 200 in 2hrs)
We had a heap of SMS still scheduled for earlier that morning, when the campaign turned off it froze the SMS, turned it back on and the scheduled SMS didnt resume.
so we have paused the campaign, scratching my head as too how scheduled SMS now works, thinking its semi connected to Campaigns but not.
Question 3
We now have a heap of scheduled SMS to go out, I have 1000 SMS still scheduled but not sending.
Keen to cut my loses and clean up things, make sure they dont magically send all of a sudden.How do we
1) backup the stats/who got what etc
and 2) bulk delete scheduled SMS “Cleanly”?
Question 4
How does the link magnification function work in sms? Is this below a bug or by design?
I had a link setup like https://tinyurl.com/api-create.php?url= setup in settings
It appears to have not respected the full URL with parameters, thus minifying before ?, and adding all our UTMs to the SMS body (assumptions were made and I added the UTMs after testing , doubling our segment twilio costs )
https://tinyurl.com/api-create.php?url=https://tornmarketing.com.au?utm_source=A
SMS body translated to https://tinyurl.com/yzhmoku9?utm_source=A
Question 5
SMS published and unpublished, what does this do?
We had unpublished sms templates still sending in campaigns.
{mautic_domain}/s/sms
Question 6
How does the sms throttling work on the twilio plugin settings, I had it configured for sending no more than 1 sms per day but the above happened