The phrase "although senior" is correct and usable in written English.
It can be used to introduce a contrast or exception regarding someone's seniority or position in a discussion or argument.
Example: "Although senior, he was open to new ideas and suggestions from the junior team members."
Alternatives: "despite being senior" or "even though he is senior."
Although senior Obama administration officials said they opposed military intervention in Syria, they did not rule out the option.
Although senior European executives at the merged exchange are based in Paris, it has adopted English as its official language.
Although senior Liberals distanced themselves from it yesterday, it was a setback for a party whose leader, Tony Abbott, has been forced to rebut allegations of misogyny.
Obama has ruled out putting US combat troops on the ground, although senior military figures have argued that air strikes will be insufficient to stop Isis.
Although senior Serbian police officials have mentioned Markovic as a suspect, no charges have been filed in the case and no body found.
In contrast, Mr. Clinton may not venture outside the Islamabad airport, although senior Administration officials said arrangements for the Pakistani visit were only now getting under way.
He said raising margin requirements would not have mattered, although senior Wall Street hands like the economist and consultant Henry Kaufman had long urged him to do so.
And although senior dancers tour on planes and learn no more roles each year than the juniors, it is even harder work.
Although senior ANP leaders have been issued police protection, the party said not enough had been done to protect its activists and candidates.
These contracts will be financed by the taxpayer, although senior administration officials have hinted broadly that Iraqi oil revenue will also be used to rebuild the country.
Although senior American officials and military officers discouraged any such bloodshed this time, they were expecting to be hailed as liberators.
