Can freckles develop with age?

Yes, aka sun damage.

Absolutely.

Freckles can be found on anyone no matter their genetic background; however, the amount of freckles is genetic… The formation of freckles is triggered by exposure to sunlight. *The exposure to UV-B radiation activates melanocytes to increase melanin production, which can cause freckles to become darker and more visible
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...Freckles are not a skin disorder, but people with freckles generally have a lower concentration of photoprotective melanin and are therefore more susceptible to the harmful effects of UV-radiation. It is suggested that they avoid overexposure and use sunscreen.

Source Surely this is not new information for you?

Yes. Freckles are melanin hot-spots. Some freckles appear at birth; others are caused by years of exposure to ultraviolet radiation from the sun.

They can and they have.

They’re also known as “age spots.” I have been wearing moisturizer with SPF since I was about 30, and my skin looks pretty good for my age, I think (and at the dermatologist’s suggestion) due to the daily SPF.

When I see people that I know laying out in the sun or tanning in a tanning booth, thinking they’re looking good with bronze skin, I know the opposite is true – because when they’re 50 and look like they’re 60, they may be sorry.

Ive never been in a tanning booth and I live in England so there is no sun. I am a red head, I have freckles because I have fair skin.

There may be very little sunlight but the UV rays still come through the cloud cover and zap your lovely skin.

Ok thats what it is, thank you

An older lady once told me that all redheads and very fair-skinned people (like me) should make sure to lotion a LOT more than other people because as we age our skin thins as well. On your arms and legs, as if brushing up against something too rough can cause you to bleed.

I developed new freckles all the time. I have one that recently developed on the tip of my big toe.

My freckles are so well-developed they have muscles.