Continental Airlines has moved swiftly to capture some of the business abandoned by strikebound sister carrier Eastern Airlines, but it disputes union claims that Continental's moves are part of a master plan to grow at Eastern's expense.

Amid its own labor problems - flight attendants on Friday ended a four-day walkout that had little impact on service - Continental has added flights on routes vacated by Eastern, taken over Eastern gates at some airports and waged an aggressive ad campaign to attract more East Coast passengers.Industry observers say the Houston-based airline has gained passengers and revenue but no more so than other competitors since Eastern virtually shut down after the March 4 strike by its machinists union and subsequent walkouts by pilots and flight attendants.

"Every carrier that still flies will be doing better now than they were before the strike, with the exception of some of the commuter lines who may have been feeding into Eastern flights," said George James, president of Airline Economics Inc. in Washington, D.C.

"So Continental will certainly see benefits, but I think that there are a number of carriers who will have far greater benefits than Continental," James said.

Eastern is reorganizing under federal bankruptcy court protection from creditors.

U.S. Bankruptcy Judge Burton R. Lifland in New York extended an order Friday forcing rival airlines to honor agreements governing ticket, baggage and cargo transfers essential to keeping strike-crippled Eastern Airlines airborne. He also barred the striking machinists from picketing on Eastern property at Logan International Airport in Boston.

Separately, a federal appeals court in Miami told a lower court to reconsider the airline's request that it force Eastern pilots back to work.

Eastern's unions have said that the parent of the two airlines, Texas Air Corp., has been trying to funnel Eastern assets to Continental, a largely non-union carrier. The machinists and Air Line Pilots Association have asked the federal bankruptcy court to appoint a trustee to govern Eastern's daily operations and business transactions, removing company management from that role.

The unions also allege that Texas Air Chairman Frank Lorenzo is using Continental as a profit-generating tool against the striking workers. But Continental officials say they - like other airlines - simply are responding to consumer demand created by the strike.