Return the next value in a list after a specific value is found

Hi, I'm probably over complicating this....

I'm trying to use Index/Match with SUMIFS to add different ranges of sequenced of values. I'm hoping to avoid using an array formula, but not a deal breaker if I need one.

Is there a formula that will sum down (and stop) at a variety of different values, then stop summing? In my example the sum starts at letter "SG" and then needs to stops at the value that comes next after "SA" which could be either and variation of "T", "h", "S", or "SG". To make things harder, I wanted the sum to also omit any rows with "V" or "X" in an adjacent column.

Attached is my example sheet.

So far I've built this formula. But I'm stuck on the "SG" string. I don't know how to find/return the next value after "SA".

N(" T >> T Stop at T (skip over h, S, SG, SA)")+
IF(C21="T",ROUND(SUMIFS(L22:INDEX(L22:L$45,IFERROR(MATCH("T",C22:C$45,)-1,)),C22:INDEX(C22:C$45,IFERROR(MATCH("T",C22:C$45,)-1,)),"<>h",C22:INDEX(C22:C$45,IFERROR(MATCH("T",C22:C$45,)-1,)),"<>S",C22:INDEX(C22:C$45,IFERROR(MATCH("T",C22:C$45,)-1,)),"<>SG",C22:INDEX(C22:C$45,IFERROR(MATCH("T",C22:C$45,)-1,)),"<>SA",E22:INDEX(E22:E$45,IFERROR(MATCH("T",C22:C$45,)-1,)),"<>V",E22:INDEX(E22:E$45,IFERROR(MATCH("T",C22:C$45,)-1,)),"<>X"),0),

N(" h >> h Stop at h (skip over S, SG, SA)")+
IF(C21="h",ROUND(SUMIFS(L23:INDEX(L23:L$46,IFERROR(MATCH("h",C23:C$45,)-1,)),C23:INDEX(C23:C$45,IFERROR(MATCH("h",C23:C$45,)-1,)),"<>S",C23:INDEX(C23:C$45,IFERROR(MATCH("h",C23:C$45,)-1,)),"<>SG",C23:INDEX(C23:C$45,IFERROR(MATCH("h",C23:C$45,)-1,)),"<>SA",E23:INDEX(E23:E$45,IFERROR(MATCH("h",C23:C$45,)-1,)),"<>V",E23:INDEX(E23:E$45,IFERROR(MATCH("h",C23:C$45,)-1,)),"<>X"),0),

N(" S or SA >> Stop at any value T, h, S, SG, or SA (+1)")+
IF(OR(C21="S",C21="SA"),ROUND(SUMIFS(L22:INDEX(L22:L$45,IFERROR(MATCH(D21+1,D22:D$45,)-1,)),C22:INDEX(C22:C$45,IFERROR(MATCH(D21+1,D22:D$45,)-1,)),"<>s",E22:INDEX(E22:E$45,IFERROR(MATCH(D21+1,D22:D$45,)-1,)),"<>V",E22:INDEX(E22:E$45,IFERROR(MATCH(D21+1,D22:D$45,)-1,)),"<>X"),0),

N(" SG >> Stop at either T, h, S, SG (skip over SA)")+
?????

Hi Glenn, I'm sorry for the confusion. My sheet was incorrect. I cleaned it up and hopefully it makes more sense now. Please disregard my first post. My sincere apologies!!

To recap my intent...
I'm in need of a formula that can sum values within a defined region (while omitting any rows that have values in column "B" and column "D"). The formula should first find/identify the next value in column "B" where the values indicate the end of the summing region (while also indicating the start of the next summing region). For example letters are used are ("T", "h", "S", "SG", or "SA".)

My formula posted above is incomplete. I only provided it because I suspect someone may suggest a better approach.

Currently I am unable to solve summing the "SG" summing region. I'm not sure how to identify which letter comes first after "SA" (which could be a variation of "T", "h", "S", or "SG"). Then based on which letter comes first, the formula would sum up to that letter.

I plan to use the formula in the yellow cells in column "G" in my sheet.

I hope this is more clear.

I wanted to offer an update. I was able to solve this myself.
My solution was to use a helper row containing a formula that provides a unique value to indicate the end of my grouping categories. With this I am able to stop my sum. I included my solution (and formulas) in my newly attached sheet.