ComboBox autotab bug(?!)

Can someone please explain this behavior?
I’ve a userform with 2 ComboBoxes. The 1st one is populated from a range of cells which contains 4 digit numbers (cells formatted as text) and has the AutoTab property set to TRUE and MaxLenght set to 4. Both ComboBoxes have TabStop property set to TRUE. When I type in this 1st ComboBox a number, it tabs automatically as expected to the 2nd ComboBox, EXCEPT if the number ends in 0. Why is that so?
What am I doing wrong?
Many thanks in advance for your help
I attached the file with this behavior.
P.S. My first POST ever.

I tested it and it works for me (MS Office Professional Plus 2016)
The Combobox also accepts data which is not in the list and changes after input of 4 characters (chars and digits) focus to the other Combobox

Thank you so much for your reply gue2013.
In my case the ComboBox also accepts data which is not in the list, including for instance, 1910, jumping for the next ComboBox after the 4th digit. However, if the data is in the list and ends with a 0, example:1530 it doesn’t jump. This happens in the following Excel versions:
Office265Pro 16.0.11929.20436 32bit
2019Pro 16.0.12527.20260 32bit
After you answer, I managed to try it in Excel2010 14.0.7237.5000 32bit and it’s working perfectly. So, I guess it’s a problem related to Excel version not the code himself