What steps do you take when working up a new batch of a load you've fully tested before, vs. starting from scratch?

E.g., last summer I worked up for my .270 Win. a load with the following components:

150-gr. Hornady SP
56.5 gr. RL-22
R-P case
CCI 200 primer

After my initial workup for pressure & velocity I did 5-shot groups for accuracy, in half-grain increments around this charge level. This was a maximum or near-maximum load in my rifle and very accurate -- sub-MOA and about 2850 fps in the summer heat.

Now I've used up that lot of powder and also have a new box of bullets, but I'm still on the same cases and primers. To save time I loaded 3 rounds each at 53.5, 54.5, 55.5 and 56.5 gr. The latter gave me perhaps 10-20 fps less velocity, but the temperature was also 30 degrees lower yesterday than it was last July.

I'm inclined to call it good and load at that level until the bullets are gone -- if I do more tests I'll burn up the rest of the box and have to start over again! But what would you do?

Generally I just take and load 5 with the new component and launch them downrange. If they group about the same as the old loads...that's the end of the testing. If they don't, well, I hope it is a nice day and you have lots of time...

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Before settling in on the load, wait till you get a similar temp day. I once did the same thing with some 7x57 loads. They did fine on a cool day, but when I fired them at 92 degrees F they flattened and cratered the primers and I had to slap the bolt open.

I am still going on record as saying this is the latest non-problem that has been pointed out to sell something. But then, I do not motor my rifles fast enough to create problems due to the weather. Since Hodgdon has "temperature insensitive" powders now, why not work up a load with one of them and kinda forget about it. Just shoot. Also, I do not rework a load if I buy a new pound of powder of the same sort. If it looks like 4350 when I open the can, I treat it like 4350. Its worked so far. No offense, but I think sometimes we spend too much time looking for cats that aren't lost.