塞尔塔主席：冬窗不会引援，我们得牢记球队没有引援名额（塞尔塔主席：冬窗不做引援，务必记住我们没有名额）

Considering transfer circumstances

I'm thinking about possible reasons for transfer restrictions: Maybe the salary cap, a full squad list, or non-EU slot limitations, indicating all 25 squad slots could be filled or the salary cap could be exceeded. Exceptions like free agents still need registration and salary room could exist. I want to keep the response concise and ask the user if they're looking for a deeper analysis or an explanation of financial rules.