Formula to return number of cells lapsed after specific reading occurred

Please try at After

D40 copy to the right
=IFERROR(ROWS(D1:D37)-MATCH(2,INDEX(1/D1:D37,)),)

D41 copy to the right
=IFERROR(ROWS(D1:D37)-MATCH(1,INDEX((ROW($E$1:$E$37)>MATCH(2,INDEX(1/D1:D37,)))/(E1:E37>0),),),)

Please try at sheet After

D40
=IFERROR(ROWS(D1:D38)-MATCH(2,INDEX(1/D1:D38/(ROW(D1:D38)<>ROWS(D1:D38)),))-1,)

D41
=IFERROR(ROWS(D1:D38)-1-MATCH(1,INDEX((ROW(D1:D38)>MATCH(2,INDEX(1/D1:D38/(ROW(D1:D38)<>ROWS(D1:D38)),)))/(OFFSET(D1:D38,,SIGN(MOD(COLUMNS($D40:D40)-2,3)-1.5))>0)/(ROW(D1:D38)<>ROWS(D1:D38)),),),)

Copy both to the right.

The formula is cover row 38, you can select row 38 and insert row or press Ctrl + when you need to add more data.

The formula in post#4 is to compare a group with 2 columns and 1 empty column between each group,
That where I use this "SIGN(MOD(COLUMNS($D40:D40)-2,3) -1.5))" for use the same formula to copy to the right.

Now you want to compare a group with 4 columns with no space column in between, that changes everything.

Group A

1 and 34 are companion numbers
24 and 26 are companion numbers

Will these changes? compare column D with E and Column C with F ?

Therefore, can we have a formula that:
1. Do not always make reference to Column D
(Since the companion numbers come in pairs, can the formula reference to only its own column and that of the companion number, rather than always Column D)

Yes. I use column D because it is the first column for formula in post#4, might change to column C.

2. Preferrably trace from bottom up rather than from the first row (because in reality there are thousands of readings continuously updated)

We can use 50 rows above current row or maybe less eg C670:C720.

Please try at C722

Formula:

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=(OFFSET(C671:C720,,-(MOD(COLUMNS($C1:C1)-1,4)-1.5)*2)
This is use for find companion column

=-(MOD(COLUMNS($C1:C1)-1,4)-1.5)*2 copy to the right gives 3, 1, -1, -3, 3, 1, -1, -3

=(OFFSET(C671:C720,,3) = F671:F720
=(OFFSET(D671:D720,,1) = E671:E720
=(OFFSET(E671:E720,,-1) = D671:D720
=(OFFSET(F671:F720,,-3) = C671:C720
=(OFFSET(G671:G720,,3) = J671:J720 and so on every 4 columns

Similar to =OFFSET(C721,,-MOD(COLUMNS($C1:C1)-1,4),,4))
This is used for find No. of cells lapsed since last reading of each group.