HELOC with Past-Due Payment History Dropped Off

[Household61974]

Sold a rental property in July that had a $4000 balance on a HELOC (no first mortgage) with BOA. 

Evidently the account, AND ITS 4 PAST DUE PAYMENTS over the last 6 years have dropped off. 

Pros and cons - I now have no mortgage in my name which affects the credit-mix portion of my score.  However, the drop of those late pays sure did give my TU FICO 8 a boost - 60 points! and have achieved the coveted 850 score! 
I don't believe (not sure) EQ and EX have picked it up yet on myFICO (scores at 810 and 815). 

I thought late pays remained on credit for 7 years, so why did this account and its payment history drop off? 

Any chance this was a TU error and they'll catch it and update?

Can we expect EQ and EX to follow suit? If so, what might we expect in the score jump with them?  

I was patting myself on the back for the TU 850. The thought of the 850 trifecta is exciting! 

[MissLiz]

I've seen posts in this forum where accounts unexpectedly came off one bureau, but remained on the others, so it's uncertain whether it will come off EX and EQ. Nonetheless, congratulations on achieving 850!