It is good that you have a regular accumulation amount that you wouldn't want to go below it. Also it is possible you may have lesser expenses and more discretionary income at some periods and you wish to increase your aggressiveness, you are still on track since you are drawing closer your accumulation target at a faster pace.
Again at some point, you may have relatively more expenses and invest lower than supposed, it is very necessary that you make up for it in preceding periods. The goal is never to leave your accumulation amounts to chance, else you might be overly whimpy in it which is not the best. Having an accumulation amount helps you remain focused and dedicated in your accumulation journey.
Mate you made a very good and versed point I love this, some investor don't understand that instead of you to do something that will make you go lower than your acumulation level, it will be better for you to maintain your present acumulation level by doing the needful, I think every investor should DCA with the amount that he or she can be comfortable with at the beginning may be go for aggressive DCA once he or she increase their income, in all what matters is consistency but one thing I know about Bitcoin investment is that as an investor you must know how to accumulate without pressure of any kind to avoid being taking some silly decisions at a point, the way we approach our investment determines if we will continue hodling for a long-term or not, as investors whose purpose of investment is for a long-term we must strategize very well on the possible way of keeping our investment intact.
You are actually right and I also share the same sentiment as you bro, the best possible way to accumulate and invest in Bitcoin is through the DCA accumulating strategy and it should be done according to how much you can afford to do away with for a very long period of time, not investing an amount that will eventually put you under unnecessary pressure because it's actually wrong to invest money you should be using for your upkeeps, or money that should be kept as part your emergency funds, because once you do that, by investing more than what you can afford to do away with for a very long time, it would be just a matter of time before you temper with your Bitcoin investment just to sorts out some basic financial needs, so in essence of what am trying to say is that while investing in Bitcoin, it's very important to invest only what you can afford to do away with, so that our discretionary income and our emergency funds will be bogus enough to carry all our financial borden's, not a situation of falling back to our holdings because of an emergency situation.