options to a contract law, ADR

[Sr Curioso]

Помогите, пожалуйста, с переводом выделенного. Какой предлог лучше?

It is allowable to apply limits 2 dB(A) higher than those stated in section 4 and clause 7.3 of this TSI for external noise from rolling stock within the scope of this specification within a transitional period of 24 months starting from the date of entry into force of this specification. This allowance is restricted to the case of contracts already signed or under the final phase of the tendering procedure at the date of entry into force of this TSI, and options to these contracts to purchase additional vehicles

Заранее спасибо

[paderin]

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