i have only a fewer Christmas cards left to write. vs i have only a less Christmas cards left to write.

Some examples from the web:

• I have only another 300 miles left to walk.
• I have only a son living.
• I have only a few minutes to finish.
• Mr President, I have only a brief remark regarding the parliamentary calendar next year.
• There is still time left to write.
• I have only one more thing left to say to you.
• There are only a few more chapters to write.
• And in any case, I have only a little neck.
• I have only a fragile existence, a mere memory self within you.
• They're expecting me at the Rezidentura. I have only a minute.
• Madam President, I have only a few brief comments to make on a report whose conclusions I largely support.
• I have only a small window of opportunity for Bombshell, and I will not have it closed.
• I have only a few comments to make on this.
• Mr President, I have only a minute, so I will be brief.
• Anyway I have only five days left To dedicate to this job
• For me I have only a week left but you have two years and a week to wait.
• But I have only a few days furlough!
• Mr President, since I have only two minutes to react, I would like to address only a few things.
• I assure colleagues that I will not start apologising for the short-sighted mean-spiritedness of the United Kingdom Government, because I have only a minute of speaking time.
• There's another card left to play.

Some examples from the web:

• You mean just one less Christmas card to me.
• You lucky, if Nathan hadn't stopped the fight, I'd have one less Christmas card to send.
• One less Christmas card I'll have to send this year.
• I have only another 300 miles left to walk.
• I have only a son living.
• I have only a few minutes to finish.
• Mr President, I have only a brief remark regarding the parliamentary calendar next year.
• There is still time left to write.
• I have only one more thing left to say to you.
• There are only a few more chapters to write.
• And in any case, I have only a little neck.
• I have only a fragile existence, a mere memory self within you.
• They're expecting me at the Rezidentura. I have only a minute.
• Madam President, I have only a few brief comments to make on a report whose conclusions I largely support.
• I have only a small window of opportunity for Bombshell, and I will not have it closed.
• I have only a few comments to make on this.
• Mr President, I have only a minute, so I will be brief.
• Anyway I have only five days left To dedicate to this job
• For me I have only a week left but you have two years and a week to wait.
• But I have only a few days furlough!