I think you cannot say categorically that this money was “linked” to a lease until the beginning of the lease. However, it could also be said that the money would not be permanently used for that lease, or even for a lease, and as such, I would say that in order to be able to definitively qualify that money as a “rental deposit”, the lease must have been executed. In the case of a common tenancy agreement, it is not certain that the provision of the prescribed information is sufficient only for one of the co-ordered tenants (z.B.dem principal tenant) to comply with the requirements of the lease bond law – the internal rules of the administrators of each system give their members some guidance, but no binding judicial decision has yet been taken on this point. Mandatory information must provide information on what has already been agreed. Do not insert new clauses and add things to the lease. Ms. S. was obliged, at every opportunity, to comply with the prescribed information because she had not done so the first time and, therefore, the amendment of the Housing Act 2004 by the Deregulation Act did not apply. Deductions from the down payment may be made in accordance with the terms of the attached lease. Full list of prescribed information that must be communicated to the tenant and anyone concerned to meet the requirements of the Rental Protection Act.
You may think it is obvious that the money is taken in advance “in connection with” the rent, but for example, if the lease would not proceed the money would be repaid, but it would not have been a rent deposit because there is no rent. The landlord (or its representative) must provide the tenant and any other “concerned person” with the required information about the approved system in which the deposit was protected.  I can understand why it is easier for owners and brokers to simply use standard formulations in their form. This saves them from having to look at the lease to check what the number of the clause is.