A little help reading the numbers on the cap

[Erin]

I received a lava lamp as a gift the other day (yay!) and I thought I had figured out the #s on the cap, but now I'm not sure.

The date on the felt bottom says either NOV 09 1999 or NOV 02 1999.

The cap reads 24 (blue water, yellow goo) and then:
990911T
090999A

I thought I read in another thread that the first set of numbers was 99 (year) and 0911 (time capped) and that the 2nd set of numbers was 090999A, meaning it was date and year capped. However, that would mean it was capped September 9th, 1999. Can the base have a different date than the cap?

Also, does anyone know what the T and A mean at the end of my two numbers on the cap?

Thanks!

[Keith]

It seems that I have added to the confusion by my post on your other thread. I searched the discussions and now think that I was wrong in suggesting the dates that I did. The one thing that seems sure is that is was made in 1999!!

[Erin]

Yeah, I think we've got the year right!

[Erin]

I just got another one tonight a #10 from 1997 that reads:
971172LV
1114COTM

Any idea what the letters mean?

[Erin]

Pretty sure. I'll take a pic tonight.

[Erin]

Here's the cap