New guidelines coming from the Civil Service Commission will permit federal agencies to put off mass downgradings of workers for up to two years.

The plan - similar to the demotion reprieve already given Health, Education and Welfare - won't be automatic or government-wide. It will permit virtually any federal agency facing major job changes (either because of reclassification of work or reorganization) to qualify for the additional time to straighten out grade levels, without demoting workers.

Studies of problem areas in problem agencies have indicated that as many as three of every 10 federal jobs may be overgraded and overpaid. Officials believe the actual picture of overgrading in government is not that bad.

Most experts agree, however, that overgrading is a serious problem in government and that it is coming to a head as agencies reorganize (or prepare to), or otherwise discover longstanding overgrading through regular desk adults of the work people are doing vs. the grades and salaries they are getting.

Normally, when a position is finally designated as overgraded the federal agency has less than 60 days to demote the employee - although pay is saved for two years.

Under the CSC guidelines, agencies will be able to request permission to delay downgrading actions if:

1) They can prove that the demotions would be widespread, disruptive to the agency mission and/or delay reorganization or be made even worse by reorganization.

2) Can assume CSC that the overgrading errors will stop immediately; that is that no other jobs will be misclassified during the demotion freeze time.

(3) Come up with a plan to straighten out existing classification errors through jet-restructing, or downgrading of positions as incumbents leave, retire or move on to other jobs.

President Carter has already promised to push Congress for legislation to restore the pay and grade of any federal worker demoted - through no fault of his or her own - since last January 1. The CSC demotion deferred guidelines are a logical extension of that plan. Several hard-nosed CSC officials including Jule Sugarman and John Cole, have held firm that the deferral action not be automatic, but something agencies must request and justify. Most, however, will be able to get it - if they try.