What Anchell says is true but not a serious concern. People use D-76 in a replenished system for months without any problem. And yes it applies to low alkalinity MQ developers for film.
D-76H should have the same activity as D-76. But it is intended to be used as a one shot and not replenished. Note that the Metol content is slightly higher than for regular D-76.
The Beutler formulla can be made as a single solution if oxygen is excluded from the solution. Tetenal did this by supplying Neofin Blue in a sealed glass ampoule. This isn't really practical for the average user hence two solutions. A similar developer Ethol TEc was supplied as a single solution in an ordinary bottle However once opened its life was rather short.
Everything considered dividimg a developer into parts really doesn't get you much. Kodak gives the shelf life of stock D-76 as 6 months. Always determine how much you mix based on how much you will use in this time period.