Cleaning data with two fields mixed in the same column?
I suggest adding a company name for each corresponding month. See the attached picture.
The formula for the first column determined if it is for a month or for the company name. Assuming that all your months are in the three-letter format and there is no company named 'May' or 'Sep', the formula for the cell B2 would be
=SUMPRODUCT(--(A2={&quot;Jan&quot;,&quot;Feb&quot;,&quot;Mar&quot;,&quot;Apr&quot;,&quot;May&quot;,&quot;Jun&quot;,&quot;Jul&quot;,&quot;Aug&quot;,&quot;Sep&quot;,&quot;Oct&quot;,&quot;Nov&quot;,&quot;Dec&quot;}))&gt;0

The formula for C2 is
=INDEX($A$2:$A$13,MATCH(2,1 /($B$2:B2=FALSE))+1)

Please refer to this page (https://www.get-digital-help.com/index-match-last-value/) for explanations for this formula.
Finally, you can filter the third column in my example to keep months for the specific company only. They will be in the order needed.