Offset every 4th row problem

Hi all,

I have a list of data - text codes - in column C.

I need column A to;

- pick up the first code in A2
- repeat that in the following 3 cells A3,A4 and A5
- THEN yellow highlighted A6 has an offset function which works, picking up the next code in cell C3
- BUT after that I want to be able to copy this set of 4 down across a long column - effectively showing each code across 4 rows
- therefore I need to figure out how the formula in cell A10 can stay referencing the next code (in cell C4) without jumping down by 3 cells and skipping some codes

Just can't figure the logic out - any help appreciated please on a hot sultry day.

Ian