You can stay more visible for longer by looking at precisely why your campaign has gotten stale. Assess which platforms are working better than others, and figure out exactly when customers are likely to take the step of searching your products and even buying one. That's not likely to be as soon as they encounter your material online, and they're going to be more inclined to do that on different platforms during different times throughout their day.
There are some really helpful insights within the full article. People who arrive at your website likely got their via several points - and very likely more than just one anyway. That makes retargeting an area that's well worth some of your focus when trying to extend the life of campaigns without refreshing their content. Concentrate on past purchasers and visitors to your site. Mix up which platforms you use to do that too. Focus on display and search audiences of between 100 and 1,000. Social platform audiences need to be a few times higher than that top figure too.
The article also explains how you can target B2B customers on Facebook. That entails a trick for combatting issues with monthly newsletter recipients. If their business email addresses don't match up with their Facebook accounts and you're trying to remarket via Facebook, that creates problems. You can get around that by making sure emails include UTM-tracked URLs. That will mean you can create a Facebook audience by targeting email traffic on your website, using a Facebook pixel placed there.
If you need some ideas, this article is full of them, and there's likely to be some you haven't tried or thought of yet. Please give it a read and let me know what you think!